One-neutron transfer study of ¹³⁷Xe and systematics of 13/2⁺₁ and 13/2⁺₂ levels in N=83 nuclei

Excited states in ¹³⁷Xe have been studied by using the near-barrier single-neutron transfer reactions ¹³C(¹³⁶Xe,¹²C)¹³⁷Xe and ⁹Be(¹³⁶Xe,⁸Be)¹³⁷Xe in inverse kinematics.Particle- and particle- coincidence measurements have been performed with the Phoswich Wall and Digital Gammasphere detector arrays. Evidence is found for a 13/2⁺₂ level (E = 3137 keV) and for additional high-lying 3/2^– and 5/2^– states. The results are discussed in the framework of realistic shell-model calculations. These calculations are also extended to the 13/2⁺₁ and 13/2⁺₂ levels in the N = 83 isotonic chain. Furthermore, they indicate that there is a need for a value of the neutron 0i_13/2 single-particle energy (E_SPE = 2366 keV) lower than the one proposed in the literature. It is also demonstr